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Available inall subroutines.

This function converts the Base64-encoded string s into a hexadecimal sequence of the same bytes. The hexadecimal sequence uses the symbols "0"–"9" to represent the values 0 to 9, and "A"–"F" to represent the values 10 to 15.

bin.base64_to_hex always uses two hexadecimal digits to represent a binary value even if the numeric value fits within one hexadecimal digit (0-F). For example, bin.base64_to_hex("AQ==") is "01".

If the Base64-encoded string s contains any null bytes, then bin.base64_to_hex does not terminate and does not return a truncated hexadecimal sequence. For example, bin.base64_to_hex("AJ/CMw==") is "009FC233".

If the Base64-encoded string s contains any non-alphabet characters, then bin.base64_to_hex terminates and returns a not set value. For example, bin.base64_to_hex("YWJ%jZA==") is a not set value.

If bin.base64_to_hex is called with a not set value or with an empty string argument, then it returns the string "". For example, bin.base64_to_hex("") is "".

To check if the return value is not an empty string or a not set value, use the std.strlen function, which returns 0 in both cases.

if (std.strlen(bin.base64_to_hex(req.http.Base64-Input)) > 0) {
    // Do something if the hexadecimal representation of the Base64-encoded
    // input string is not an empty string or a not set value.
}

Errors

If the Base64-encoded string s is not valid Base64, then fastly.error will be set to EINVAL.

Examples

bin.base64_to_hex("AQIDBAUGBwgJ") # returns "010203040506070809"
bin.base64_to_hex("AJ8AwgAzAA==") # returns "009F00C2003300"
bin.base64_to_hex("-YWJjZA==") # returns a not set value and fastly.error is "EINVAL"
bin.base64_to_hex("") # returns ""
bin.base64_to_hex(not set string) # returns a not set value
bin.base64_to_hex("YWJjZA==") # returns "61626364"